Motorized Zone Valves - how they work

Hi, I know nothing on this subject so please bare with me. I live in an apartment and the baseboard heaters have just been hooked up. They use a hot water system with a Honeywell motorized zone valve. The heat was on 24hrs/day although my thermostat was at 0. I peeked inside the baseboard and there's a switch that says AUTO on one side and OPEN/MAN on the other. It was on MAN. So I pushed it the other way on the AUTO side when the heating finally stopped. However, if I turn up the thermostat higher than the room temperature, heat doesn't come on. It will only come back on when I manually set the switch back to MAN where it slowly slides back to AUTO on its own.

My question is, if I want to regulate the heat with my thermostat, where should the switch be, MAN or AUTO? I'm used to electric baseboards so this is completely foreign territory.

thank you

 

Actually I hadn't noticed the little dent where that AUTO - MAN switch is. I can leave it on MAN w/o it sliding back to the other side on its own. I still don't get the AUTO vs MAN functioning with the thermostat though.

 

Manual is usually used for filling and venting systems so the water can pass into the zone the valve is on while the power is off. It should normaly be left in the auto position so when the timer/clock is turned on power is sent to your room stat. When the room stat is turned up it will send power to the motor inside the zone valve which will open the flow to the zone.

The problem could be at any of these componants.

Andy.

 

The motors are powered from a 24VAC transformer somewhere in the system. Some installers provide fuses on the thermostat wiring to protect the transformers from shorts. Could be a bad fuse, or even a bad transformer if someone shorted the 24VAC. Just a few other things to check...

Pete